--- /dev/null
+/* Copyright (c) 2013-2014. The SimGrid Team.
+ * All rights reserved. */
+
+/* This program is free software; you can redistribute it and/or modify it
+ * under the terms of the license (GNU LGPL) which comes with this package. */
+
+#include "colls_private.h"
+
+int flattree_segment_in_byte = 8192;
+
+int
+smpi_coll_tuned_bcast_flattree_pipeline(void *buff, int count,
+ MPI_Datatype data_type, int root,
+ MPI_Comm comm)
+{
+ int i, j, rank, num_procs;
+ int tag = COLL_TAG_BCAST;
+
+ MPI_Aint extent;
+ extent = smpi_datatype_get_extent(data_type);
+
+ int segment = flattree_segment_in_byte / extent;
+ segment = segment == 0 ? 1 :segment;
+ int pipe_length = count / segment;
+ int increment = segment * extent;
+ if (pipe_length==0) {
+ XBT_WARN("MPI_bcast_flattree_pipeline use default MPI_bcast_flattree.");
+ return smpi_coll_tuned_bcast_flattree(buff, count, data_type, root, comm);
+ }
+ rank = smpi_comm_rank(comm);
+ num_procs = smpi_comm_size(comm);
+
+ MPI_Request *request_array;
+ MPI_Status *status_array;
+
+ request_array = (MPI_Request *) xbt_malloc(pipe_length * sizeof(MPI_Request));
+ status_array = (MPI_Status *) xbt_malloc(pipe_length * sizeof(MPI_Status));
+
+ if (rank != root) {
+ for (i = 0; i < pipe_length; i++) {
+ request_array[i] = smpi_mpi_irecv((char *)buff + (i * increment), segment, data_type, root, tag, comm);
+ }
+ smpi_mpi_waitall(pipe_length, request_array, status_array);
+ }
+
+ else {
+ // Root sends data to all others
+ for (j = 0; j < num_procs; j++) {
+ if (j == rank)
+ continue;
+ else {
+ for (i = 0; i < pipe_length; i++) {
+ smpi_mpi_send((char *)buff + (i * increment), segment, data_type, j, tag, comm);
+ }
+ }
+ }
+
+ }
+
+ free(request_array);
+ free(status_array);
+ return MPI_SUCCESS;
+}